JP2013004148A - Optical transmission module, and manufacturing device and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical transmission module capable of adjusting the positions of a semiconductor laser and an optical waveguide with high accuracy by a simple operation, a manufacturing device thereof and a manufacturing method thereof.SOLUTION: The optical transmission module includes a semiconductor laser fixed to a submount and an optical waveguide part having a light incident surface and a light outgoing surface, and has a structure in which the submount is adhered to the optical waveguide part. The optical waveguide part has an optical waveguide extending from the light incident surface to the light outgoing surface, and a plurality of reflection parts exposing themselves to the light incident surface. When viewed at the light incident surface, the optical waveguide and first two reflection parts among the plurality of reflection parts are arranged on the same straight line, and the optical waveguide and second two reflection parts different from the two reflection parts among the plurality of reflection parts are arranged on the same straight line different from a straight line. The position of the optical waveguide is detected from the positions of the four reflection parts, and the relative inclination of the semiconductor laser and the optical waveguide part is set to the minimum from the light quantity balance of the semiconductor laser reflected by the four reflection parts.

Description

  The present invention relates to an optical transmission module applicable to a head gimbal assembly or the like of a thermally assisted magnetic recording apparatus, a manufacturing apparatus thereof, and a manufacturing method thereof.

In recent years, a heat-assisted magnetic recording system has been proposed as a recording system that achieves a recording density of 1 Tb / in ² or more (Non-Patent Document 1). In the conventional magnetic recording, when the recording density is 1 Tb / in ² or more, loss of recorded information due to thermal fluctuation becomes a problem. To prevent this, it is necessary to increase the coercive force of the magnetic recording medium, but since the magnitude of the magnetic field that can be generated from the recording head is limited, if the coercive force is increased too much, a recording bit is formed on the medium. It becomes impossible to do. In order to solve this problem, in the thermally assisted magnetic recording method, the magnetic recording medium is heated with light at the moment of recording to reduce the coercive force. As a result, recording on a high coercive force medium is possible, and a recording density of 1 Tb / in ² or more can be realized.

  In this heat-assisted magnetic recording, the spot diameter of the irradiated light needs to be the same size (several tens of nm) as the recording bit. This is because information on adjacent tracks is erased if the light spot diameter is larger than that. Near-field light is used to heat such a minute region. Near-field light is a localized electromagnetic field (light having wavenumber having an imaginary component) existing in the vicinity of a minute object having a wavelength equal to or smaller than the light wavelength, and is generated using a minute aperture or a metal scatterer having a diameter equal to or smaller than the light wavelength. For example, it has been proposed to use a triangular metal scatterer as a highly efficient near-field light generating element (Non-Patent Document 2). When light is incident on the metal scatterer, plasmon resonance is excited in the metal scatterer, and strong near-field light is generated at the apex of the triangle. By using this near-field light generating element, light can be collected with high efficiency in a region of several tens of nm or less. In other words, the heat-assisted magnetic recording head requires an optical transmission module that efficiently guides light to the near-field generator.

  As such an optical transmission module, Patent Document 1 discloses a slider having a magnetic head portion in which an optical waveguide is provided at a position close to an electromagnetic coil element in the stacking direction of the magnetic head, and this slider. A heat-assisted magnetic recording head including a light source unit in which a light source is provided on a light source support substrate is disclosed. In this configuration, the light emitted from the light source can be introduced into the optical waveguide and emitted from the light exit surface of the optical waveguide in the medium facing surface, whereby the magnetic recording medium can be locally heated.

  In Patent Document 2, a plurality of optical waveguides and a light absorption layer are formed in the slider for alignment (alignment) of the slider and the light source unit, and a light amount monitor is disposed on the medium facing surface of the slider during alignment to sequentially receive light. By checking this, high-precision alignment of the semiconductor laser and the slider in the plane direction is realized.

JP 2006-185548 A JP 2009-54206 A

Jpn. J. Appl. Phys. 38, Part 1, p.1839 (1999) Technical Digest of 6th international conference on near field optics and related techniques, the Netherlands, Aug. 27-31, 2000, p.55

  Here, in order to produce the optical transmission module described in Patent Document 1, it is necessary to hold the light source unit after being stacked on the surface (back surface) opposite to the medium facing surface of the slider. In this case, after the slider and the light source unit having the magnetic head portion are independently tested, the non-defective slider and the light source unit are held, and the optical transmission module can be manufactured with a high yield. Further, in this case, since the light source can be provided at a position away from the medium facing surface and in the vicinity of the slider, there is almost no problem such as a decrease in light propagation efficiency or a complicated configuration of the entire apparatus. However, when the slider and the light source unit are separately manufactured as described above, it is necessary to accurately align the light source and the optical waveguide when fixing the slider and the light source unit. There is no specific description of the structure and assembly method of the optical transmission module.

  On the other hand, in Patent Document 2, a plurality of optical waveguides are formed so as to be the same layer in the film forming process at the time of manufacturing a magnetic head for alignment, and a light absorption layer is formed by film formation before and after the plurality of optical waveguides. The structure of a specific optical transmission module to be formed is shown. By using the above structure, the semiconductor laser (light source in Patent Document 2) and the slider can be aligned with high accuracy. However, Patent Document 2 does not have a mechanism for adjusting the relative tilt between the semiconductor laser and the slider. In a structure in which an objective lens or the like is not used when light from a semiconductor laser is incident on an optical waveguide provided on a slider as in Patent Document 2, a semiconductor laser is used to allow a sufficient amount of light to enter the optical waveguide provided on the slider. And the slider must be close to a few μm. The structure of the semiconductor laser is a square shape with one side of the emission side of about several hundred μm. When the semiconductor laser is tilted several degrees with respect to the slider, not only the amount of light that can enter the optical waveguide provided in the slider is reduced, but also the worst case. In this case, the semiconductor laser and the slider are in physical contact, and any element is damaged. In the above document, in order to facilitate assembly, the semiconductor laser is attached to the light source support substrate in a separate process before the semiconductor laser is held on the slider. However, when this light source support substrate is bonded to the slider, a slight inclination occurs between parts during curing shrinkage of the adhesive due to uneven application of the adhesive and the position dependence of the curing conditions. There is no. That is, in Patent Document 2, it is difficult to determine whether the detected light amount has decreased due to the position or inclination between components.

  As a problem other than the alignment method, there is an addition of a light source support substrate. Since the weight of the entire light transmission module is increased by adding the light source support substrate, it is difficult to fly the slider stably. Further, since the height of the heat-assisted magnetic recording head is increased by the thickness of the light source support substrate, the recording capacity per volume is reduced in a magnetic disk device storing a plurality of disks and heads.

  Therefore, the present invention provides a mechanism capable of adjusting not only the position but also the tilt of the semiconductor laser and the optical waveguide portion in a structure without a light source support substrate, and can easily align the semiconductor laser and the optical waveguide with a simple operation. An object of the present invention is to provide an optical transmission module, a manufacturing apparatus thereof, and a manufacturing method thereof that can be adjusted with accuracy.

  An optical transmission module of the present invention is an optical transmission module that includes a semiconductor laser held on a submount and an optical waveguide portion having a light incident surface and a light output surface, and the submount is fixed to the optical waveguide portion. The optical waveguide portion is arranged so that the light incident surface faces the semiconductor laser, and includes an optical waveguide extending from the light incident surface toward the light emitting surface, and a plurality of reflecting portions exposed to the light incident surface. And when viewed from the light incident surface, the first two reflecting portions of the optical waveguide and the plurality of reflecting portions are arranged on the first straight line, and the optical waveguide and the plurality of reflecting portions are The second two reflecting parts different from the two reflecting parts are arranged on a second straight line different from the first straight line, and the semiconductor laser is bonded and held to the optical waveguide part via the submount. Yes.

  The plurality of reflecting portions may be formed along the optical waveguide from the light incident surface to the light emitting surface. By forming the first two reflective portions on a first layer different from the layer of the optical waveguide, and forming the second two reflective portions on a second layer different from the optical waveguide and the first layer The four reflecting portions can be easily manufactured by two film forming processes when the optical waveguide portion is manufactured. Preferably, the four reflecting portions are centered on the optical waveguide and arranged on an elliptical orbit that is a contour line of luminance at the light spot of the semiconductor laser used in the optical transmission module, so that the emission point of the semiconductor laser is the optical waveguide. Since the amount of reflected light from the four reflecting portions can be made equal when the extension axis coincides and the relative inclination between the semiconductor laser and the optical waveguide portion is 0 °, that is, parallel, The assembly accuracy can be improved by monitoring the amount of reflected light.

  An optical transmission module manufacturing apparatus according to the present invention includes a first holding part that holds a submount, a light source provided in the first holding part, a second holding part that holds an optical waveguide part, and a second Fine adjustment moving part that can adjust the position and angle of the holding part, a first light detector for monitoring light from the light source and the semiconductor laser, and a position and angle of the first light detector can be adjusted Movable unit, a second photodetector for monitoring the output of the light source, a third photodetector for monitoring the light reflected from the optical waveguide unit by the semiconductor laser, and the first photodetector A first calculation unit that calculates relative position and relative tilt information of the light source and the semiconductor laser using luminance distribution data acquired by adjusting the position and angle of the semiconductor by the moving unit, and the semiconductor held by the first holding unit Held in the second holding part while driving the laser The position information of the plurality of reflecting portions provided in the optical waveguide portion with respect to the light source is obtained using the luminance distribution data obtained by moving the waveguide portion by the fine adjustment moving portion and acquired by the second photodetector. A second calculation unit for calculating the position of the optical waveguide formed in the optical waveguide unit from the plurality of reflection units by the third photodetector while driving the semiconductor laser held by the first holding unit. A third calculation unit that detects a reflected light amount of the second holding unit and calculates an angle of the second holding unit for minimizing a relative angle between the semiconductor laser and the optical waveguide unit from a relationship between the reflected light amounts from the plurality of reflection units; Using the information obtained by the first calculation unit and the information obtained by the second calculation unit, the optical waveguide unit is finely adjusted so that the emission point of the semiconductor laser coincides with the extension axis of the optical waveguide. After moving in the moving part, the information obtained in the third calculating part is By adjusting the relative tilt between the optical waveguide unit and the semiconductor laser using a fine adjustment moving unit, an optical transmission module in which the relative tilt between the optical waveguide unit and the semiconductor laser is less than a desired angle, preferably 2 ° or less. To manufacture.

  The light source provided in the first holding unit can be a collimated light source. The first photodetector can be an image sensor. The second photodetector may be a photodiode provided in the light source, and the third photodetector includes four photodiodes and a signal calculation circuit that calculates detection signals of the four photodiodes. Can be.

  In the optical transmission module manufacturing method according to the present invention, the submount to which the semiconductor laser is fixed is held by the first holding unit, the collimated light source and the semiconductor laser provided in the first holding unit are driven, A first step of calculating a relative position and a relative inclination between the collimated light source and the semiconductor laser based on the luminance distribution data detected by the photodetector; and driving the collimated light source and placing the second holding unit below the collimated light source By detecting the output of the collimated light source with the second photodetector while two-dimensionally moving the held optical waveguide portion, the positions of the plurality of reflecting portions provided in the optical waveguide portion are detected. The second step of calculating the position of the optical waveguide having a known positional relationship with the light, and the light in which the light emitting point of the semiconductor laser is provided in the optical waveguide unit based on the information acquired in the first and second steps Adjusting the position and angle of the second holding part so as to coincide with the extension axis of the waveguide, and detecting the reflected light of the semiconductor laser by the plurality of reflecting parts provided in the optical waveguide part with a third photodetector; A third step of adjusting the inclination of the optical waveguide portion by the second holding portion so that the reflected light from the plurality of reflection portions is balanced, and a fourth step in which the submount is bonded and fixed to the optical waveguide portion in this state Steps.

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing apparatus and manufacturing method of an optical transmission module and the optical transmission module can be provided.
Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

Schematic which shows the structural example of a hard-disk apparatus. The perspective schematic diagram which shows the structural example of an optical transmission module. The cross-sectional model which shows the structural example of an optical transmission module. The model of the slider for optical transmission modules seen from the semiconductor laser opposing surface. The schematic diagram of the semiconductor laser fixed to the submount. The block diagram which shows the structural example of an optical transmission module manufacturing apparatus. Explanatory drawing of the 1st process by the optical transmission module manufacturing apparatus. The figure which shows light quantity distribution detected at 1 process of the 1st process. The figure which shows light quantity distribution detected at 1 process of the 1st process. The figure which shows light quantity distribution detected at 1 process of the 1st process. Explanatory drawing of the 2nd process by the optical transmission module manufacturing apparatus. The figure which shows light quantity distribution detected by the 2nd process. Explanatory drawing of the 3rd process by an optical transmission module manufacturing apparatus. The figure which shows the structural example of the photodetector in a 3rd process. The figure which shows the light quantity distribution simulation result in the slider surface at the time of a 3rd process. The figure which shows the detection signal of a detector when inclining a slider to x direction in the case of a 3rd process. The figure which shows the detection signal of a detector when a slider is inclined in ay direction in the case of a 3rd process. The figure which shows the inclination dispersion | variation of the produced optical transmission module. The schematic diagram which shows the other structural example of an optical transmission module. The figure which shows the other structural example of an optical transmission module manufacturing apparatus. The figure which shows the inclination dispersion | variation of the produced optical transmission module. The flowchart which shows the 1st process of the optical transmission module manufacturing method. The flowchart which shows the 2nd process of the optical transmission module manufacturing method. The flowchart which shows the 3rd process of the optical transmission module manufacturing method.

  Preferred embodiments of the present invention will be described with reference to the drawings. Note that in the drawings, the same reference numerals are used for the same elements or elements having the same function, and redundant description is omitted. Further, the dimensional ratios in the components and between the components in the drawings are arbitrary for easy viewing of the drawings.

  Below, the manufacturing method of an optical transmission module is demonstrated. Embodiment 1 shows an example of an optical transmission module used for a heat-assisted magnetic recording head, and Embodiment 2 shows an example of an optical transmission module used as a light source integrated optical fiber. In addition, since the optical waveguide part used in this Embodiment 1 turns into a magnetic head part provided with the electromagnetic transducer in addition to the optical waveguide, Embodiment 1 demonstrates an optical waveguide part as a magnetic head.

[Embodiment 1: Thermally assisted magnetic recording head]
[1] Configuration of Head Gimbal Assembly and Hard Disk Device First, the configuration of the hard disk device will be described with reference to FIG. The semiconductor laser mounted slider 1 is held by a suspension 3 and is positioned at a desired track position on the magnetic disk 2 by an actuator comprising a voice coil motor 4. A flying pad was formed on the head surface, and the magnetic disk 2 was floated with a flying height of 10 nm or less. The magnetic disk 2 is held and rotated by a spindle 5 that is rotationally driven by a motor. The drive driver for the semiconductor laser was disposed on the circuit board. The circuit board was also equipped with a driver for the magnetic head. The recording signal was generated by the signal processing LSI 6, and the recording signal and the power for the semiconductor laser were supplied to the driver for the semiconductor laser through an FPC (flexible printed circuit). At the moment of recording, a magnetic field was generated by a coil provided in the semiconductor laser-mounted slider 1, and at the same time, a semiconductor laser was emitted to form a recording mark. Data recorded on the magnetic disk 2 was reproduced by a magnetic reproducing element (GMR or TMR element) formed in the slider 1 mounted with the semiconductor laser. The signal processing of the reproduction signal was performed by a signal processing circuit.

  The head gimbal assembly (HGA) has a configuration in which an optical transmission module serving as a semiconductor laser mounting slider 1 is attached to the tip of the suspension 3.

[2] Configuration of Optical Transmission Module Next, the configuration of the optical transmission module will be described with reference to FIGS. As shown in FIG. 2, the optical transmission module includes a slider substrate 10 and a slider having a magnetic head unit 9 for writing and reading data signals, and a light source having a semiconductor laser 7 and a submount 8 for holding the semiconductor laser 7. With units. The slider substrate 10 or the magnetic head unit 9 and the submount 8 are fixed by an adhesive 11 such as a UV curable epoxy resin or a UV curable acrylic resin.

[2.1] Slider The slider substrate 10 is plate-shaped as shown in FIG. The medium facing surface S of the slider substrate 10 is processed into a predetermined shape so that the heat-assisted magnetic recording head can obtain an appropriate flying height. The slider substrate 10 can be formed of conductive Altic (Al ₂ O ₃ .TiC) or the like. A near-field light generating element 13 for generating near-field light for heating the recording layer portion of the magnetic disk is disposed in the vicinity of the medium facing surface S of the slider. Although not shown, in the vicinity of the near-field light generating element 13 Is provided with an electromagnetic conversion element. The electromagnetic transducer is configured by laminating a recording element composed of a single magnetic pole head and a reproducing element composed of a CPP / GMR type sensor element. On the rear surface F opposite to the medium facing surface S of the slider, a semiconductor laser 7 emitting light having a wavelength of 780 nm fixed to the submount 8 as a light generating / introducing element (light source) is passed through a cured adhesive 11 ′. The light emitted from the semiconductor laser 7 is applied to the near-field light generating element 13 through the optical waveguide 12. The optical waveguide 12 is placed around a Ta ₂ O ₅ core having a long side of 500 nm, a short side of 300 nm, and a refractive index of 2.18 so as to be in a single mode with respect to light having a wavelength of 780 nm. 5 is a structure covered with a cladding made of SiO ₂ . In this optical waveguide 12, the mode diameter of guided light is substantially the same as the size of the waveguide core. That is, the energy of the guided light is substantially confined in the core.

As shown in FIG. 3, the optical waveguide 12 is disposed between the reading head unit and the recording head unit, and extends from the medium facing surface S to the back surface F so as to be parallel to the integration surface. . Therefore, the end surface on the medium facing surface S side of the optical waveguide 12 is exposed to the medium facing surface S, and the end surface on the back surface F side faces the laser light emitting surface of the semiconductor laser 7. The back surface F is substantially parallel to the medium facing surface S. In this embodiment, Ta ₂ O ₅ (refractive index = 2.18) is used as the core material of the optical waveguide 12 and SiO ₂ (refractive index = 1.5) is used as the cladding material. greater if the core and cladding material than the refractive index of the cladding may be other materials, such as SiO ₂ with respect to the cladding of (refractive index = 1.5), the core Al ₂ O ₃ (refractive index = 1.6 ), TiO ₂ (refractive index = 2.4), or the like. The material of the cladding may be MgF ₂ (refractive index = 1.4) whose refractive index is smaller than that of SiO ₂ . Further, as the material of the core, it may be used SiO ₂ doped with other materials such as Ge.

  The near-field light generating element 13 is made of gold (Au) in the shape of an isosceles triangular prism, and has a base of 100 nm, a hypotenuse of 130 nm, and a height of 200 nm. The apex portion of the isosceles triangular prism is processed into an arc having a radius of curvature of about 10 nm, and the spot diameter of the generated near-field light is about 25 nm. In order to improve the coupling efficiency when light from the semiconductor laser 7 is incident on the optical waveguide 12, a spot diameter conversion mechanism or the like is preferably formed immediately below the laser diode unit. By irradiating the light coupled to the optical waveguide 12, the near-field light generating element 13 generates near-field light on the surface of the magnetic disk according to a principle such as plasmon resonance, and the temperature of the medium surface rises. When the power of light applied to the near-field light generating element 13 is about 10 mW, the local temperature of the medium magnetic film rises to about 200 ° C. At the same time, the temperature of the near-field light generating element 13 increases by about 150 degrees, and the resistance of the near-field light generating element 13 increases due to the influence of heat scattering.

  Four reflecting portions 14 are provided at a distance of 100 to 200 μm from the optical waveguide 12. However, since FIG. 3 is a sectional view, only two are displayed in FIG. Since the four reflecting portions 14 need to have a higher reflectance than the surrounding regions, when the surrounding regions are made of the same material as the cladding of the optical waveguide 12, the optical waveguide 12 is used as the material of the four reflecting portions 14. The core material was used. As other materials, the use of a high reflectivity metal used for the near-field light generating element 13, Cu used for wiring in the slider, or a metal material for forming a coil is simple in terms of the film forming process. A reflection part can be produced.

  FIG. 4 is a schematic view of the slider as seen from the semiconductor laser facing surface. The arrangement of the optical waveguide and the four reflecting parts will be described with reference to FIG. When the magnetic head portion 9 of the slider is viewed from the semiconductor laser facing surface (F in FIG. 3), the four reflecting portions 14a to 14d centering on the optical waveguide 12 are arranged on the elliptical orbit EO. The size of each reflecting portion was 10 μm long and 1 μm wide. The width direction corresponds to the thickness at the time of film formation when the magnetic head portion is formed, and it is difficult to increase this value in the film formation process, but when detecting using an image sensor such as a CCD during alignment. In consideration of optical resolution, it was designed to be 1 μm. At this time, two reflecting portions 14a and 14c of the four reflecting portions are arranged on the straight line 2 so as to face each other with the optical waveguide 12 interposed therebetween. The other two reflecting portions 14b and 14d are arranged on a straight line Line1 different from Line2 so as to face each other with the optical waveguide 12 interposed therebetween. Further, two of the four reflecting portions 14a and 14b are simultaneously formed as the reflecting layer L1 when the magnetic head is manufactured, and the remaining two reflecting portions 14c and 14d are different from the reflecting layer L1. It is formed as a layer L2.

[2.2] Light Source Unit As shown in FIG. 5, in the light source unit, the semiconductor laser 7 is fixed on the submount 8, and the semiconductor laser 7 has a substantially rectangular parallelepiped shape. The submount 8 is a conductor formed of Altic (Al ₂ O ₃ · TiC) or the like. The semiconductor laser 7 can be the same as the semiconductor laser having a multiple quantum well structure used for the optical information recording medium. In these semiconductor lasers, a reflective film 15 made of SiO ₂ , Al ₂ O ₃ or the like for exciting oscillation due to total reflection is formed before and after the cleavage plane of the multilayer structure. One reflective film is provided with an opening at a position corresponding to the active layer, and a region corresponding to the opening in the surface on which the reflective film 15 is formed emits a laser beam 16. It becomes. In such a semiconductor laser 7, a laser beam is emitted from the light emitting point 16 by applying a voltage in the film thickness direction. The semiconductor laser 7 may have another configuration using another semiconductor material such as a GaAlAs system. The metallized layer 18 is provided to physically fix the semiconductor laser 7 to the submount 8 and to form an electrical contact with the bottom surface of the semiconductor laser, and a solder material such as AuSn can be used.

  The semiconductor laser 7 is formed into a chip with work accuracy such as cleavage and mounted on the submount 8. Therefore, when the cross-section is observed, the semiconductor laser 7 is not a rectangle but a shape with rounded corners of a parallelogram or a parallelogram. Often becomes. Therefore, it is difficult to search for the light emitting point 16 with reference to the outer shape and edge of the semiconductor laser 7. Therefore, at the time of alignment, in order to search for the light emitting point 16 of the semiconductor laser 7, the relative position between the mesa structure 17 and the light emitting point 16, which is a design parameter, is referred to based on the concave mesa structure 17 formed in the semiconductor laser 7. By doing so, the light emitting point 16 can be easily searched. The wavelength λ of the emitted laser light is, for example, about 780 nm to 850 nm. However, an appropriate excitation wavelength corresponding to the metal material of the near-field light generating element 13 exists, and the design wavelength of the optical waveguide must be noted. For example, in this embodiment, λ = 780 nm is set in accordance with the design wavelength of the optical waveguide, but it has been confirmed that this wavelength also operates in the near-field light generating element 13 using Au.

  The size of the semiconductor laser 7 can be set to, for example, a width of 200 μm to 350 μm, a length of 200 μm to 400 μm, and a thickness of about 60 μm to 200 μm. Here, the width of the semiconductor laser 7 can be reduced to, for example, about 100 μm, with the interval between the opposing ends of the current blocking layer as a lower limit. However, the length of the semiconductor laser 7 is an amount related to the current density and cannot be made so small. In any case, it is preferable that the semiconductor laser 7 has a considerable size in consideration of handling during mounting. However, in particular, the length of the semiconductor laser is a parameter that determines the thickness of the entire slider, and in the present embodiment in which no light source support substrate other than the submount is used, it is difficult to increase it to 400 μm or more from the viewpoint of the flying characteristics of the slider. . In this embodiment, the semiconductor laser 7 having a width of 200 μm, a length of 250 μm, and a thickness of 100 μm is used.

[3] Optical Transmission Module Manufacturing Apparatus and Manufacturing Method Next, an optical transmission module manufacturing apparatus and manufacturing method will be described with reference to FIGS. 6 to 16 and FIGS. 20 to 22. First, a slider including the magnetic head portion having the above-described configuration and a semiconductor laser fixed to the submount having the above-described configuration are manufactured. Subsequently, alignment of the magnetic head portion and the semiconductor laser is performed by the following optical transmission module manufacturing apparatus and the optical transmission module manufacturing method shown in FIGS.

  As shown in the block diagram of FIG. 6, the optical transmission module manufacturing apparatus holds the semiconductor laser 7 fixed to the submount 8 by the first holding unit 19 that holds the submount. The first holding unit 19 is equipped with a holding unit-attached light source unit 21 and a second photodetector. In the present embodiment, a semiconductor laser with a back monitor in which a collimator lens and a beam shaping prism are combined is used as the holding unit-attached light source unit 21 and the second photodetector. The collimator lens is an optical element for collimating the emitted light emitted from the semiconductor laser, and the beam shaping prism is, in principle, different beam spread in the direction parallel to the direction parallel to the reflective layer of the semiconductor laser. An optical element having the same angle. The back monitor is a photodiode disposed in the vicinity of the semiconductor laser. By using the back monitor, the amount of light emitted from the semiconductor laser can be monitored.

  The second holding unit 25 that holds the magnetic head unit includes a fine adjustment moving unit 24 that adjusts the angle and position of the second holding unit 25 and a fine adjustment moving unit controller. In this apparatus, by using the back monitor and the fine adjustment moving unit, the positions of the four reflecting units formed on the magnetic head unit can be detected.

  In addition, the apparatus includes a holding unit-attached light source unit 21 and a first photodetector 23 for monitoring the light of the semiconductor laser 7, and a moving unit 22 that adjusts the position of the first photodetector 23. And a moving unit control device. In the present embodiment, an image sensor such as a CCD is used as the first photodetector 23. By using the image sensor, it is possible to observe the light spot position and the light spot shape of the light source unit 21 attached to the holding unit and the semiconductor laser 7, and the light source unit 21 attached to the holding unit and the semiconductor laser can be analyzed by analyzing the observation result. 7 relative position and inclination can be detected.

  Furthermore, a third photodetector for monitoring the light reflected from the magnetic head unit by the semiconductor laser 7 is provided. In the present embodiment, four photodiodes and a signal arithmetic circuit are used.

  It is the control PC that calculates the signals of the first to third photodetectors and controls each moving unit controller for assembly. The control PC includes the first to third calculation units. Embedded as software. In the first calculation unit, the first photodetector 23 detects the spot of the semiconductor laser 7 held by the first holding unit 19 and the spot of the light source unit 21. Further, the first holding unit 19 holding the semiconductor laser 7 is scanned using the moving unit 22. In this way, the relative position and relative tilt information of the light source unit 21 and the semiconductor laser 7 are calculated using each luminance distribution data acquired by the first photodetector 23. The second calculation unit scans the magnetic head unit using the fine adjustment moving unit 24, and uses the luminance data at each position acquired by the second photodetector to magnetic head for the light source unit 21 attached to the holding unit. The position information of the four reflecting portions 14a to 14d provided in the portion is calculated. And the position of the optical waveguide 12 with which the magnetic head part was equipped is estimated from the known positional relationship with respect to the four reflection parts 14a-14d. In the third calculation unit, the semiconductor laser 7 is driven, the reflected light amounts from the four reflection units 14a to 14d are acquired by the third photodetector, and the calculated light amount balance signal is used for the semiconductor laser 7. Minimize the relative angle of the magnetic head.

  In the first embodiment, an optical transmission module in which the relative angle of the magnetic head unit with respect to the semiconductor laser is reduced by the following first to third processes using the optical transmission module manufacturing apparatus. The manufacturing method will be described in detail below.

[3.1] First Process The first process shown in FIG. 20 is performed with the second holding unit 25 retracted as shown in FIG.

  Both the semiconductor laser 7 held by the first holding unit 19 and the holding unit-attached light source unit 21 fixed to the first holding unit 19 are the first photodetector 23 using the moving unit 22. The image sensor was brought close to the camera (S11). This is executed by instructing the moving unit control device from the control PC and driving the moving unit 22 by the moving unit control device in accordance with the instruction. Subsequently, the control PC drives the laser driver to turn on the light source unit 21 and the semiconductor laser 7 at the same time (S12). Thereby, the first photodetector 23 detects the light spots of the semiconductor laser 7 and the light source unit 21, and the first photodetector transmits the detected luminance distribution data to the control PC (S13). The control PC detects the relative position and the relative inclination of the semiconductor laser 7 and the light source unit 21 by the first calculation unit according to the procedure shown in FIGS. 8A to 8C (S14).

  First, as shown in FIG. 8A, the light amount distribution on the first photodetector 23 when the light source unit 21 and the semiconductor laser 7 are turned on in the initial state is acquired. On the first photodetector 23, the light spot S1 of the light source unit 21 and the light spot S2 of the semiconductor laser 7 are observed. By the apparatus calibration, the relative position and inclination of the first photodetector 23 and the light source unit 21 in the initial state are managed. Since a collimated light source that has been subjected to beam shaping is used as the light source unit 21, as shown in FIG. 8A, the shape of the light spot S1 of the light source unit 21 is a perfect circle, and the luminance distribution is point-symmetric about the luminance peak point. It becomes. On the other hand, the shape of the light spot S2 of the semiconductor laser 7 is different in the beam divergence angle in the direction perpendicular to the direction parallel to the reflection layer of the semiconductor laser in principle, and therefore the spot shape observed by the first photodetector 23. Has an elliptical shape. In addition, the semiconductor laser 7 usually has a slight inclination with respect to the light receiving surface of the first photodetector 23 in response to the difference in the handling state of the first holding unit 19 due to variations in the external dimensions of the semiconductor laser. Yes. Therefore, the luminance distribution of the light spot S2 of the semiconductor laser 7 is observed as a distribution having an inclination rather than a point symmetry with respect to the luminance peak point. In this state, the first calculation unit of the control PC can detect the relative positions Δx and Δy of the light spot S1 of the light source unit 21 and the light spot S2 of the semiconductor laser 7.

  Subsequently, as shown in FIG. 8B, the moving unit 22 was scanned so that the light spot S <b> 2 of the semiconductor laser 7 was at the center of the light receiving surface of the first photodetector 23. 8C, the luminance distribution of the light spot S2 of the semiconductor laser 7 is obtained by moving the inclination of the light receiving surface of the first photodetector 23 by Δθx and Δθy using the moving unit 22. Adjustments can be made to be point-symmetric about the luminance peak point. At this time, the relative inclinations of the light spot S1 of the light source unit 21 and the light spot S2 of the semiconductor laser 7 can be detected as -Δθx and -Δθy.

  Thereafter, the control PC stores and stores information on the relative position and relative tilt between the detected light source unit and the semiconductor laser in the memory (S15), instructs the moving unit control device, and drives the moving unit 22 to perform the first operation. The photodetector 23 is retracted (S16).

[3.2] Second Process The second process shown in FIG. 21 is performed with the first photodetector 23 retracted, as shown in FIG.

  Using the fine adjustment moving unit 24, the slider (optical waveguide unit) 10 held by the second holding unit 25 is brought close to the light source unit 21 fixed to the first holding unit 19 (S21). This is executed by instructing the fine adjustment moving unit controller from the control PC, and the fine adjustment moving unit controller drives the fine adjustment moving unit 24 and moves the second holding unit 25 in accordance with the instruction. Subsequently, the control PC drives the laser driver to turn on only the light source unit 21 (S22). And the emitted light quantity of the light source unit 21 is acquired with the 2nd photodetector incorporated in the light source unit 21. FIG. Subsequently, the luminance data acquired by the second photodetector incorporated in the light source unit 21 is transmitted to the control PC while moving the slider 10 held by the second holding unit 25 using the fine adjustment moving unit 24. . In this way, the control PC acquires the detected light amount distribution as shown in FIG. 10 (S23).

As shown in FIG. 10, in the detected light amount distribution, four regions where the detected light amount decreases are detected. The second calculation unit of the control PC obtains the center coordinates (x ₁ , y ₁ ), (x ₂ , y ₂ ), (x ₃ , y ₃ ), (x ₄ , y ₄ ) of these four regions. And obtained as position coordinates of the four reflecting portions 14a to 14d when viewed from the reference with the light source unit as the origin. The reason why the center coordinates of the region where the detected light amount decreases corresponds to the position coordinates of the four reflecting portions 14a to 14d will be described below.

The amount of light detected by the back monitor reflects the amount of light emitted from the semiconductor laser included in the light source unit 21, but the laser oscillation is unstable when the light emitted from the semiconductor laser returns to the element. Thus, in the case of a semiconductor laser that emits light with the same drive current control, the light emission power decreases. In the present embodiment, when the return light to the light source unit 21 becomes large, that is, when the fine adjustment moving unit 24 is moved and the coordinates of the light source unit 21 and the reflecting units 14a to 14d coincide with each other, a decrease in detection power is confirmed. did it. When the semiconductor laser is caused to emit light with the same drive power control, the amount of detected light increases conversely when there is return light. In any case, by performing the above-described measurement, the position coordinates (x ₁ , y ₁ ), (x ₂ , y ₂ ) of the four reflecting portions 14a to 14d when viewed from the reference with the light source unit 21 as the origin. , (X ₃ , y ₃ ), (x ₄ , y ₄ ). Since the optical waveguide 12 exists at the center position surrounded by the four reflecting portions, the second calculation unit of the control PC calculates the coordinates (x, y) of the optical waveguide 12 as follows (S24). .
(X, Y) = ((x ₁ , y ₁ ) + (x ₂ , y ₂ ) + (x ₃ , y ₃ ) + (x ₄ , y ₄ )) / 4
The control PC stores the information of the calculated coordinates (x, y) of the optical waveguide 12 in a memory and saves it (S25).

[3.3] Third Process The third process shown in FIG. 22 is performed with the first photodetector 23 retracted, as shown in FIG.

  First, based on the information obtained in the first process and the second process, the light emitting point of the semiconductor laser 7 is provided in the magnetic head portion in a state where the tilts of the semiconductor laser 7 and the slider 10 are matched. It arrange | positions so that it may correspond with the extension axis | shaft of the waveguide 12. FIG. For this purpose, the control PC uses the relative position and relative tilt information of the light source unit 21 and the semiconductor laser 7 acquired in the first process to instruct the fine adjustment movement unit controller to drive the fine adjustment movement unit 24. The position and inclination of the semiconductor laser 7 and the slider 10 are corrected by adjusting the position and inclination of the second holding unit 25 (S31). In addition, the control PC uses the positional information of the optical waveguide 12 acquired in the second process to instruct the fine adjustment moving unit control device to drive the fine adjustment moving unit 24, and thereby position the semiconductor laser 7 and the optical waveguide 12. Matching is performed (S32).

  Next, the control PC instructs the fine adjustment moving unit control device to drive the fine adjustment moving unit 24, and the slider 10 held by the second holding unit 25 is held by the first holding unit 19. It is brought close to the semiconductor laser 7 (S33). Then, the control PC turns on only the semiconductor laser 7 by driving the laser driver (S34).

  Here, as shown in FIG. 12, the third photodetector is configured by four photodiodes 27 a to 27 d and a signal calculation processing unit 28. The four photodiodes 27a to 27d are arranged at positions where the semiconductor laser 7 can detect the reflected light from the four reflecting portions 14a to 14d provided in the magnetic head portion of the slider, and each of the photodiodes 27a to 27d. The obtained signals A, B, C, and D are transferred to the signal calculation processing unit 28, and the signal calculation processing unit 28 calculates a light quantity balance signal BS according to the following equation. In the equation, Avarage (A: D) means an average value of the acquired signals A to D by the four photodiodes 27a to 27d.

  The data of the light quantity balance signal BS is transmitted from the third photodetector to the control PC. The control PC instructs the fine adjustment moving unit control device to drive the fine adjustment moving unit 24 to incline the sliders held by the second holding unit 25 by slightly tilting them in the x and y directions. In step S35, the light quantity balance signal BS is acquired. The third calculation unit of the control PC is a second holding unit for setting the relative inclination of the magnetic head unit and the semiconductor laser to several degrees or less, preferably 2 degrees or less, based on the angle dependency of the light quantity balance signal BS. 25 rotation angles in the x and y directions are obtained (S36). Next, the control PC instructs the fine adjustment moving unit control device to drive the fine adjustment moving unit 24 and set the second holding unit 25 to the angle obtained by the third calculation unit (S37).

  FIG. 13 shows a light quantity distribution simulation result on the slider surface in the third process when there is no relative tilt between the magnetic head portion and the slider. In the PD1, PD2, PD3, and PD4 regions on the slider surface in the figure, the emitted light from the semiconductor laser is reflected by the reflecting portions 14a to 14d provided in the magnetic head portion and detected by the photodiodes corresponding to each. The In the present embodiment, since the optical waveguide and the four reflecting portions are arranged on an elliptical orbit that is centered on the optical waveguide and becomes a contour line of luminance in the light spot of the semiconductor laser used for the heat-assisted magnetic recording head, the magnetic head When there is no relative tilt between the part and the slider, the brightness at PD1, PD2, PD3, and PD4 has the same value as shown in FIG. Therefore, the tilt condition that minimizes the light quantity balance signal BS during alignment is that there is no relative tilt between the magnetic head unit and the semiconductor laser.

  Subsequently, when the laser driver is driven to turn on only the semiconductor laser 7 and the fine adjustment moving unit 24 is used to scan the relative inclinations θx and θy of the magnetic head unit (slider), the third photodetector is used. FIG. 14 and FIG. 15 show the light quantity balance signal BS detected in this way. FIG. 14 is a diagram illustrating the light quantity balance signal BS when the magnetic head unit is tilted in the down track direction (x direction), and FIG. 15 is a diagram when the magnetic head unit is tilted in the cross track direction (y direction). It is a figure which shows the light quantity balance signal BS. In the figure, the horizontal axis represents θx or θy, and the vertical axis represents the normalized signal intensity.

  14 and 15, the light quantity balance signal BS is minimized in that the relative inclination between the magnetic head unit and the semiconductor laser 7 becomes zero as described above. On the other hand, in comparison with FIG. 14, in FIG. 15, the inclinations of the detection signals A, B, C, D and the light quantity balance signal BS of each photodetector are smaller. This is considered to depend on the beam divergence angle of the semiconductor laser 7. In addition, the detection signals A, B, C, and D of the respective photodetectors are maximized because the relative tilt between the magnetic head and the semiconductor laser is not zero but at an angle tilted to some extent. This is because the luminance peak point shown in FIG. 13 approaches one of the photodetectors when the semiconductor laser is tilted. In either case of FIG. 14 or FIG. 15, it was found that the relative inclination of the magnetic head portion and the semiconductor laser is several degrees or less in the region where the light quantity balance signal BS is 10% of its maximum value. .

  When the relative inclination and position of the semiconductor laser and the magnetic head portion are specified in this way, the adhesive 11 is cured by curing on the back surface of the slider substrate 10 and the bonding surface of the submount 8 as shown in FIG. A UV curable adhesive was applied. Examples of the UV curable adhesive include UV curable epoxy resins and UV curable acrylic resins.

  Then, the amount of light incident on the near-field light generating element 13 from the optical waveguide 12 is monitored by the temperature detecting element provided in the near-field light generating element 13, and the detected light amount is maximized, that is, the light emitted from the semiconductor laser 7. Fine adjustment of the alignment of the magnetic head portion and the semiconductor laser was performed so that the point overlapped with the optical waveguide 12, and the back surface of the slider substrate 10 and the bonding surface of the submount were overlapped at that position. Thereafter, the UV curable adhesive was cured by irradiating the UV curable adhesive from the outside to adhere the slider substrate 10 and the submount 8. Thereafter, a heat assist magnetic recording head gimbal assembly is formed by adding a flexure part and a suspension as in the conventional optical transmission module.

  FIG. 16 shows the result of cross-sectional SEM (SEM: Scanning Electron Microscope) observation of 20 manufactured heat-assisted magnetic recording head gimbal assemblies, and examining the relative tilt between the semiconductor laser and the magnetic head portion. In the present embodiment, the relative tilt between the semiconductor laser and the magnetic head portion can be made 2 ° or less. The relative tilt between the semiconductor laser and the magnetic head is greater in the down track direction (x direction) than in the cross track direction (y direction). The tilt of the light quantity balance signal BS is in the down track direction (x direction). This is because it was difficult to adjust the tilt.

[4] Operation Next, the operation of the optical transmission module according to the present embodiment will be described.
At the time of writing or reading operation, the optical transmission module floats with a predetermined flying height hydrodynamically on the surface of the rotating magnetic disk. At this time, the reading head unit and the recording head unit on the medium facing surface S side face the magnetic disk through a minute spacing, thereby reading by sensing the data signal magnetic field and writing by applying the data signal magnetic field. And done. Here, as shown in FIG. 3, when writing a data signal, the laser light propagating from the semiconductor laser 7 through the optical waveguide 12 reaches the near-field light generating element 13, and from the near-field light generating element 13. Near-field light is generated. This near-field light enables heat-assisted magnetic recording. Then, by adopting a heat-assisted magnetic recording system, writing is performed on a magnetic disk with high coercive force using a thin film magnetic head for perpendicular magnetic recording, and the recording bit is made extremely fine, for example, 1 Tb / in ^2. Class recording density can be achieved.

  As mentioned above, although the embodiment in which the present invention is applied to the thermally-assisted magnetic recording head has been described in detail, the present invention is not limited to the above-described embodiment. For example, in the present embodiment, the near-field light generating element 13 has a triangular shape. However, the near-field light generating element 13 may have a concave shape or a trapezoidal shape. A structure called a bow-tie type in which a pair is arranged so as to face each other at a predetermined distance may be used. Further, the near-field light generating element 13 can be an opening smaller than the wavelength of the laser light. In the present embodiment, the electromagnetic transducer has a configuration in which a recording element composed of a single magnetic pole head and a reproducing element composed of a CPP / GMR type sensor element are laminated. However, the recording element can have various structures. A single-layer thin film coil or two or more thin-film coils may be provided, and a helical coil may be used. Similarly, the reproduction sensor includes a GMR (Giant Magneto Resistive) element utilizing a giant magnetoresistive effect having a high magnetoresistance change rate, an AMR (Anisotropy Magneto Resistive) element utilizing an anisotropic magnetoresistive effect, and a magnetism generated at a tunnel junction. A TMR (Tunnel Magneto Resistive) element using a resistance effect, a CPP (Current Perpendicular to Plane) -GMR element, or the like may be used. Moreover, you may reproduce | regenerate using light. By detecting the rotation of the polarization of the return light from the recording bit, the magnetization direction of the recording bit can be detected. The semiconductor laser drive driver and magnetic head driver used in this embodiment may be integrated into an IC chip together with the signal processing LSI and mounted in the middle of the suspension.

  In this embodiment, the light source unit in the optical transmission module manufacturing apparatus is a semiconductor laser in which a collimator lens and a beam shaping prism are combined. However, a fiber light source with a collimator lens may be used. In addition, although the back monitor provided in the semiconductor laser is used as the second photodetector, a detection photodetector may be arranged in the first holding unit. In the present embodiment, the first photodetector and the slider are moved using the moving unit and the fine adjustment moving unit, but if the relative positions and inclinations of the first holding unit and the second holding unit can be adjusted, The moving unit and the fine adjustment moving unit may be in the first holding unit. However, since it is necessary to inject current into the semiconductor laser or the like in the first holding unit, it is preferable not to provide the moving unit or the like in the first holding unit as in this embodiment. In this embodiment, paying attention to the luminance distribution of the semiconductor laser, the positions of the optical waveguide 12 and the four reflecting portions 14 are arranged on the elliptical orbit EO, but the amount of reflected light at each point is calculated by simulation or the like in advance. It is also possible to estimate the relative inclination between the same semiconductor laser and the magnetic head part using the correction light quantity balance signal by storing the value in the control PC and performing the correction calculation in the third calculation part. Is possible. In this embodiment, the temperature detection element provided in the near-field light generating element 13 is used for fine adjustment of the alignment between the magnetic head portion and the semiconductor laser. However, an optical waveguide for light detection is built in the slider, and the external light A detector may be used.

[Embodiment 2: Light source integrated optical fiber]
Embodiment 2 shows an example of a light source integrated optical fiber using an optical fiber for the optical waveguide portion. In a general light source integrated optical fiber, in addition to the semiconductor laser and the optical fiber, a condensing lens for condensing the light of the semiconductor laser onto the optical fiber is necessary, and alignment work of these three components is necessary. It was. Also, the element size when integrated is increased. By using the present invention, an optical transmission module can be easily manufactured without a condensing lens, so that the cost and size of the optical transmission module can be reduced.

  The configuration of the optical transmission module will be described with reference to FIG. As shown in FIG. 17, the optical transmission module includes an optical fiber 29, an optical fiber coating portion 30, an optical waveguide portion 32 having a reflection portion 31, a semiconductor laser 7, and a submount 8 that holds the semiconductor laser 7. A light source unit. The optical fiber covering portion 30 to the reflection portion 31 that are optical waveguide portions and the submount 8 are fixed by an adhesive 11 such as a UV curable epoxy resin or a UV curable acrylic resin. The description of the semiconductor laser 7 is omitted because there is no structural difference from the first embodiment. Of course, the wavelength may be different from that of the semiconductor laser of the first embodiment, or the size may be different. On the light incident surface of the optical waveguide portion 32, the optical fiber 29 and the plurality of reflecting portions 31 disposed around the optical fiber 29 have a known positional relationship.

  Next, with reference to FIG. 18, a manufacturing apparatus and a manufacturing method of the optical transmission module according to the second embodiment will be described. Descriptions of parts common to the first embodiment in both the manufacturing apparatus and the manufacturing method are omitted.

  First, the optical waveguide part 32 having the reflection part 31 and including the optical fiber 29 and the semiconductor laser 7 fixed to the submount 8 are manufactured. Subsequently, the alignment between the optical waveguide portion 32 and the semiconductor laser 7 was performed by the first to third processes using the optical transmission module manufacturing apparatus, as in the first embodiment. As shown in FIG. 18, since the optical waveguide portion 32 has a long optical waveguide length unlike the slider of the first embodiment, the second holding portion 25 has a structure for grasping the outer periphery of the optical fiber coating portion.

  FIG. 19 shows the result of cross-sectional SEM observation of 20 manufactured light source integrated optical fibers, and examining the relative inclination between the semiconductor laser and the optical waveguide portion. In the present embodiment, the relative inclination between the semiconductor laser and the optical waveguide portion can be made 1 ° or less. Compared to the first embodiment, the magnitude of the relative inclination is smaller because, unlike the small magnetic head unit, in the second embodiment, the large optical fiber coating portion is arranged with a large area of the reflective portion at a distance, so that the relative inclination is slightly smaller. This is because a large change in the balance signal BS can be detected even when an inclination occurs.

  In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

DESCRIPTION OF SYMBOLS 1 Semiconductor laser mounting slider 2 Magnetic disk 3 Suspension 4 Voice coil motor 5 Spindle 6 Signal processing LSI
7 Semiconductor Laser 8 Submount 9 Thermally Assisted Magnetic Recording Head 10 Slider Substrate 11 Adhesive 11 ′ Adhesive Cured Product 12 Optical Waveguide 13 Near-Field Light Generating Elements 14a to 14d Reflector 15 Reflective Film 16 Light-Emitting Point 17 Mesa Structure 18 Metallized Layer 19 First holding unit 20 Semiconductor laser 21 Light source unit 22 Moving unit 23 First photodetector 24 Fine adjustment moving unit 25 Second holding unit 27a to 27d Photodiode 28 Signal calculation processing unit 29 Optical fiber 30 Optical fiber coating Part 31 Reflecting part 32 Optical waveguide part

Claims (14)

An optical transmission module comprising a semiconductor laser held by a submount, and an optical waveguide portion having a light incident surface and a light exit surface, wherein the submount is fixed to the optical waveguide portion,
The optical waveguide portion is disposed such that the light incident surface faces the semiconductor laser, and an optical waveguide extending from the light incident surface toward the light emitting surface, and a plurality of exposed light guide surfaces. Having a reflective part,
When viewed from the light incident surface, the optical waveguide and the first two reflecting portions of the plurality of reflecting portions are arranged on a first straight line, and the optical waveguide and the plurality of reflecting portions are arranged. The second two reflecting portions different from the two reflecting portions are arranged on a second straight line different from the first straight line,
The optical transmission module, wherein the semiconductor laser is bonded and held to the optical waveguide portion through the submount. The optical transmission module according to claim 1,
The plurality of reflecting portions are formed along the optical waveguide from the light incident surface to the light emitting surface. The optical transmission module according to claim 1 or 2,
The first two reflecting portions are formed in a first layer different from the layer of the optical waveguide, and the second two reflecting portions are second different from the optical waveguide and the first layer. An optical transmission module characterized in that the optical transmission module is formed in a layer. The optical transmission module according to any one of claims 1 to 3,
When viewed from the light incident surface, the plurality of reflecting portions are arranged on an elliptical orbit that is centered on the optical waveguide and that is a contour line of luminance in the light spot of the semiconductor laser. module. An apparatus for manufacturing an optical transmission module, wherein a submount for holding a semiconductor laser is fixed to an optical waveguide portion in which an optical waveguide is formed, and laser light generated from the semiconductor laser is incident on the optical waveguide of the optical waveguide portion In
A first holding unit for holding the submount;
A light source provided in the first holding unit;
A second holding part for holding the optical waveguide part;
A fine adjustment moving part capable of adjusting the position and angle of the second holding part;
A first photodetector for monitoring light from the light source and the semiconductor laser;
A moving unit capable of adjusting a position and an angle of the first photodetector;
A second photodetector for monitoring the output of the light source;
A third photodetector for monitoring light reflected from the optical waveguide portion by the semiconductor laser;
A first calculator that calculates relative position and relative tilt information of the light source and the semiconductor laser using luminance distribution data acquired by adjusting the position and angle of the first photodetector by the moving unit;
While driving the semiconductor laser held by the first holding unit, the optical waveguide unit held by the second holding unit is moved by the fine adjustment moving unit and acquired by the second photodetector. A second position of acquiring position information of a plurality of reflecting portions provided in the optical waveguide portion with respect to the light source using the luminance distribution data, and calculating a position of the optical waveguide formed in the optical waveguide portion from the position information A calculation unit;
While driving the semiconductor laser held by the first holding unit, the amount of light reflected from the plurality of reflecting units is detected by the third photodetector, and the amount of light reflected from the plurality of reflecting units is detected. A third calculation unit for calculating an angle of the second holding unit for minimizing a relative angle between the semiconductor laser and the optical waveguide unit from a relationship;
Using the information obtained by the first calculation unit and the information obtained by the second calculation unit, the optical waveguide unit is moved so that the emission point of the semiconductor laser coincides with the extension axis of the optical waveguide. After moving by the fine adjustment moving unit, correcting the relative inclination between the optical waveguide unit and the semiconductor laser using the fine adjustment moving unit based on the information obtained by the third calculation unit. An optical transmission module manufacturing apparatus for manufacturing an optical transmission module in which a relative inclination between the optical waveguide portion and the semiconductor laser is less than a desired angle. In the optical transmission module manufacturing apparatus according to claim 5,
The light transmission module manufacturing apparatus, wherein the light source provided in the first holding unit is a collimated light source. In the optical transmission module manufacturing apparatus according to claim 5 or 6,
The optical transmission module manufacturing apparatus, wherein the first photodetector is an image sensor. In the optical transmission module manufacturing apparatus according to any one of claims 5 to 7,
The apparatus for manufacturing an optical transmission module, wherein the second photodetector is a photodiode provided in the light source. In the optical transmission module manufacturing apparatus according to any one of claims 5 to 8,
The third optical detector includes four photodiodes and a signal calculation circuit that calculates detection signals of the four photodiodes.   The optical transmission module manufacturing apparatus according to any one of claims 5 to 9, wherein the desired angle is 2 °. Luminance distribution data detected by a first photodetector that holds a submount to which a semiconductor laser is fixed by a first holding unit, drives a collimated light source provided in the first holding unit and the semiconductor laser. A first step of calculating a relative position and a relative inclination between the collimated light source and the semiconductor laser based on:
The collimated light source is driven, and the output of the collimated light source is monitored by a second photodetector while two-dimensionally moving the optical waveguide section held by the second holding section below the collimated light source. A second step of detecting the positions of a plurality of reflecting portions provided in the waveguide portion and calculating the positions of the optical waveguides having a known positional relationship with respect to the plurality of reflecting portions;
Based on the information acquired in the first and second steps, the position and angle of the second holding part so that the light emitting point of the semiconductor laser coincides with the extension axis of the optical waveguide provided in the optical waveguide part. And the reflected light of the semiconductor laser by the plurality of reflecting portions provided in the optical waveguide portion is detected by a third photodetector, and the reflected light from the plurality of reflecting portions is balanced. A third step of adjusting the inclination of the optical waveguide part by two holding parts;
A fourth step of adhering and fixing the submount to the optical waveguide portion in that state;
A method of manufacturing an optical transmission module, comprising: In the manufacturing method of the optical transmission module according to claim 11,
The first photodetector is an image sensor;
The relative position and relative inclination of the collimated light source and the first photodetector are configured in an initial state,
In the first step, in order to obtain a relative position between the collimated light source and the semiconductor laser, the first photodetector is arranged so that the luminance center of the semiconductor laser is located at the center of the first photodetector. In order to obtain a relative inclination between the collimated light source and the semiconductor laser, and the inclination of the first photodetector is symmetric with respect to the luminance peak point. A method of manufacturing an optical transmission module, comprising adjusting In the manufacturing method of the optical transmission module according to claim 11,
In the second step, the reflecting unit utilizes the fact that the output of the collimated light source monitored by the second photodetector changes due to the return light from the reflecting unit entering the collimated light source. A method for manufacturing an optical transmission module, comprising: detecting a position of the optical transmission module. In the manufacturing method of the optical transmission module according to claim 11,
In the third step, the amounts of reflected light from the four reflection portions detected by the third photodetector are A, B, C, D, and the average value of the reflected amounts of light A to D is Avarage (A : D), the optical transmission module manufacturing method is characterized in that the inclination of the optical waveguide portion is adjusted so that the light quantity balance signal BS of the following formula is minimized.

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